Watch this

In his latest wheat/chaff sifting exercise, Sugar sends the teams to Bluewater. Here, they must encourage the tanned and the Ugged to pay for "photographic portraits". A tricky task made impossible, as recalcitrant laptops, mutiny and the breathtaking hopelessness of team leader Simon, pictured below ("I've got an IQ of 170!"), conspire to turn the venture into Project Doom.

Dan Cruickshank's Adventures in Architecture

9pm, BBC2

"It's rational! Elegant! And strong!" emotes the historian about an elderly mosque, hands and vowels whizzing like Catherine wheels. Clearly, much the same could be said of Cruickshank: a presenter whose whirling adjectival energy could convert the staunchest disbeliever. Among the destinations tonight: a Chinese temple, an Egyptian monastery and a Russian church that resembles a hill of ossified onions.

Child Genius

9pm, Channel 4

A year after we left them scowling over their equations, we revisit the nippers whose unusually big brains have seen each lumbered with the titular mantle. There are, clearly, worse crosses to bear, though the sight of Georgia's mother beaming as she describes her toddler's "white aura" may inspire feelings of fear and loathing. But the largest crikeys are reserved for the microboffins' astonishing self-belief. "Even if I shattered down completely with nerves, I'd still crush them," peeps putative chess champ Peter of his rivals, as his unsmiling father nods in agreement. Brrr.

Indiana Jones: The True Story

9pm, Five

Following C4's Quest for the Lost Ark, here is more excitable, covenant-related conjecture. Tonight, a question mark revolves over the identity of the real-life adventurer who inspired the creation of Spielberg's conspicuously non-real-life adventurer. Was it Roy Chapman Andrews - 1920s daredevil, archaeologist and consummate lady-appreciator? Perhaps. Less likely a candidate is Otto Rahn, whose tenuous similarities to the titular swashbuckler - interested in the Holy Grail, had a hat, once ran out of a cave - are nevertheless stuffed like kapok into the documentary's remaining spaces. Of which there, are, alas, many.